In a current radio communication system such as a Long Term Evolution (LTE), a precoding matrix codebook is preliminarily stored in a radio base station and a mobile station, and then, a codeword used such that the mobile station communicates with the radio base station is selected from the preliminarily stored codebook, in accordance with, for example, a channel state of the mobile station. In order to fast and efficiently select the codeword used such that the mobile station communicates with the radio base station, from the preliminarily stored codebook, in a future radio communication system such as a LTE-Advanced (LTE-A) subsequent to the LTE, the following method has already been proposed; the method first elementary selects the codewords included in the codebook, and then, further selects the codeword that the mobile station uses from the elementarily selected codewords.
Considering application to various applied situations, the precoding matrix master codebook and different setting of the master codebook may be used to generate different codebooks for different applied situations. Specifically, the master codebook is preliminarily stored in the radio base station and the mobile station. The radio base station may determine a configuration-entry codebook that the radio base station and the mobile station can use during actual data transmission, via a configuration entry corresponding to an actual situation. The codeword in this configuration-entry codebook may be a subset of the codewords in the master codebook. The radio base station transmits information of the configuration entry to the mobile station such that the mobile station precisely generates the configuration-entry codebook. In this description, terms such as “a configuration entry,” “a configuration item,” “a configuration,” and “configured” can be interchangeably used.